Method of making jewelry chains



Patented May 14, 1935 UNITED STATES PATENT OFFICE 1 Claim.

This invention relates to a chain mainly designed for jewelry purposes,the general object of the invention being to provide a flexible core anda plurality of tubular members placed on the core to provide a tubechain.

This invention is a continuation in part of an application filed by meon May 1'7, 1934, Serial No. 726,151.

This invention also consists in'certain other features of constructionand in the combination and arrangement of the several parts, to behereinafter fully described, illustrated in the accompanying drawing andspecifically pointed out in the appended claim.

In'describing the invention in detail, reference will be had to theaccompanying drawing wherein like characters denote like orcorresponding parts throughout the several views, and in which:

Fig. 1 is an elevation of a length of chain constructed in accordancewith this invention.

Fig. 2 is a fragmentary view, with parts in section.

Fig. 3 is a view, with the tube in section, showing how the tube is cutinto short lengths by a spinning operation.

Fig. 4 is a fragmentary longitudinal sectional view, the section beingtaken at right angles to that of Fi 2.

In this drawing, the numeral I indicates a chain which is composed ofthe links 2 having rounded ends, and in carrying out the invention, aplurality of short tubes 3 is placed on the chainso that the chain formsa core or filler and each end of each tube has an inwardly extendingpart 4 ment on thechain.

which is engaged by a rounded link of the chain. so that each tube hasbut limited sliding move- I The invention is carried out by placing anelongated tube over the chain and then cutting the tube into shortlengths and deforming the ends to provide the inwardly extending parts 4which limit sliding movement of the tubes on the chain.

This operation is performed by a spinning process as shown in Fig. 3,which shows one part of a tube being separated from another part by thespinning action of a rotating member 5 carried by a shaft 6. Thisspinning process displaces the middle of the tube inwardly until a pointis reached where the metal parts; so that one part of the tube isseparated from another part, the displaced metal extending inwardly toform the inwardly extending portions 4. Of course, as many of themembers 5 are used as are necessary to divide the tube into the desirednumber of parts.

The tube is severed at points which intersect certain of the linksmidway between the ends of said links as shown in Figs. 2 and 4 andduring the spinning operation, the side members of said links areindented as shown at I by the spinning actions. The beveled spinningwheel leaves the ends of the tube sections slightly beveled as shown.

I claim:

The herein described method of forming a tube chain consisting inplacing a long tube over a chain, then cutting the tube into shortlengths by spinning operations which press the metal at the ends of theshort lengths inwardly to form interior projections at the ends of theshort lengths, said projections engaging portions of the chain.

FREDERICK W. BOPP.

